I can't be the only one with this little problem.

With the stereo about 1/2 throttle and above the lights dim. even at 40 to 50 mph. I really noticed it last night for some reason. I have always seen it at idle, but rarely noticed it at higher speeds.

05 F150 5.4 FX4, amps are Rockford Fosgate 1001bd bridged to single channel powering 2 10" RF HX2 in a supercrew sound box. The other amp is a Sony 4 channel GT460 I think. It runs the 5x7 JBL in the rear and the Polk momo 6500 in the fronts. Kenwood head unit.

Do i need a cap or is there another remedy for this, not sure I have room for a cap.

 

try doing the big 3 upgrade...if your not familiar with this term search and around here and get the specifics...should cure that problem pretty easily as you shouldnt have that much dimming. i would stay away from the cap, if you want to add anything look into a second battery.

 

forget the cap. dont add it. i cant find it now but im sure someone has the link proving they are worthless if not bad.

 

As suggested, try the big three upgrade first, along with making sure you have solid connections on all power wires, and a GOOD SOLID ground.

If you have a smaller alternater from the factory, or are running some other electrical items (efans, driving lights, etc) then you may just be plumb outta juice and need a bigger alternater.

 

Big 3 upgrade, high output alternator, better battery, or what I did was put an overdrive pulley on the factory alternator. It keeps my power up around 13.8-14.5 amps depending on how much bass I have turned on.

Ive learned from experience that trying to run a system of 1000+ watts will within a couple months leave you stranded with a bad alternator. But for some reason with the over drive pulley, I went over a year with no problems but then sold the car. And I had a much more powerful system in my mustang then in my truck.

Also try turning your amp down and turning the bass on your headunit up instead of using your amp for the majority of your bass.

 

optima yellow top.

my previous system was hilarious, if i cranked it all the way (i rarely did) everytime the bass would hit hard the lights would flicker, so my headlights/tailights would pulse with the music.

 

Add a Kinetik HC600 "Cap Killer" battery to the system. I use these all the time. It is equivalent to one hundred 1 farad capacitors. Small enough to mount behind your seat. Measuring only (L x W x H) 7" x 3" x 6.5"

 

This is a link that was posted to my question about geting a cap, and it surely changed my mind.
http://forum.realmofexcursion.com/sh...ad.php?t=17970

 

I can tell you first hand that the HX2's consume a whole lot of power. I had two of hooked up to get a 2 ohm load on a JL 500/1 with the gain not even turned up half way my headlights and interior lights will dim. Those subs are borderline SPL subs. I took two IDQ's and replaced them in the same box at a 2 ohm load, not only did the subs sound better, I had no dimming issues. Also you should try one of those old school RF amps. I had a 225 around the basement and they seem to work great together.

 

I found the thread that descibed the three changes, I will look into doing it.

What are you using for cables? Am I just running a jumper from the Alt to the Bat. in addition to the original wiring?

 

yep, 1/0 gauge all around. the way i did mine is this: ground= body to engine to frame to battery negative. positve= alt to positve battery. simple, took me bout an hour from start to finish.